Water-tight explosive cartridge



Dec. 13, 1932. w R, i E 1,8WL7Z6 WATER TIGHT EXPLOSIVE CARTRIDGE I FiledAug. 20, 1930 INVENTOR. W/u MM If, EARRE/V,

A TTO RNE Y.

atented ec. 13, 1932 at are WILLIAM R. FARREN, OF TAMAQUA, PENNSYLVANIA,ASSIGNOR TO ATLAS IOWDER COMPANY, OF \VILMINGTON, DELAWARE, ACORPORATION OF DELAWARE WATER-TIGHT EXPLOSIVE CARTRIDGE Applicationfiled August 20, 1930. Serial'No'. 476,631.

l frequently has to be given to the question of whether the explosive issufficiently res stant to the water likely to be encountered rather thanto whether the explosive is the most efficient or the most economical.For instance,

there are frequent cases where expensive gelatin dynamites are used forwork which definitely demands black powder or low density ammoniumnitrate dynamites, and where the most marked economy could be effectedby the substitution of the latter for the said gelatin dynamites.

As is well known, the explosives commonly employed for blasting are inthe form of sticks composed of fairly heavy paper wrap-- pers, filledwith the explosive and waterproofed to a limited extent by being dippedin parafiin after the paper wrappers have been closed. As theresult ofextensive experiments, I have evolved the hereinafter described methodof assembling explosives in cartridge form by packaging them in aspecially prepared flexible wrapper, which takes the place of the paperwrapperhez'etofore used, and which yields a cartridge capable ofresisting the entry of water, even in the .presence of decided externalpressures.

The application of Roy Linden Hill, Serial Number 436,888, filed on the18th day of March, 1930, covers the broad thought of an assembly of thegeneral character of that herein described, the present inventionresiding more particularly in the improvement of a very simple andeconomical means for expeditiously sealing the wrapper.

In the accompanying drawing Fig. 1 is a vertical sectional View, and

Fig. 2 is a side elevation of an explosive assembly constructed inaccordance with the invention.

In the drawing, 5 designates the main body of explosive material, and 6represents a re- V ceptacle for the same, which is, preferably, in thenature of a rubberized water-proof and moisture-proof fabric. Thisfabric may be rubberized on either or both sides. If rubberized on onlyone side, the uncoated side is disposed toward the outside of thecartridge so that'water will not be' carried to the explosive, .bycapillarity. The important feature constituting the subj ect matter ofthe present invention resides in the provision of a sealing meanspreferably at each end of the assembly consisting of a plug 8, which is,preferably, of rubber or like compressible, water-proof resilientmaterial, about which the free upper end of the fabric of the receptaclemay be gathered, as indii cated at 9, such gathered-portion being bound,forcibly, into water-tight union with the plug 8, by a wire or othercompression strand 10, the ends of which are twisted together to theextent necessary to secure the desired drawing and binding action uponthe strand. The water-proof union between the cloth and the plug isproduced jointly by the tension of the wire or strand 10, and theelasticity of'the rubber plug, these two forces acting in o positedirections against the rubberized fa ric. To facilitate the applicationof the wire strand, its ends are, preferably, looped, as indicated at11, to facilitatethe engagement of a tool therewith. However, it is tobe understood that the invention is not limited to any particular typeof strand, nor to any particular material for the same. I contemplate.the use of any band adapted to exert a drawing action about the plug.However, the provision of the ends of the wire with the loops shown, isof utility in that these loops serve the double function of .providingengaging means for a tool, and of providing elements which may beengaged by a hook, or other lowering device for loading the explosiveinto deep holes where dropping might cause -ruptures, and thus destroythe water-proof container. It will be observed that the plug 8 will beof considerably smaller diameter than the sheath 6 and thus thesupporting loops 11 may be caused to lie wholly within the projectingplane of the side wall of the sheath so that there will be no drag onthese loops or the suspension hook attached thereto, upon the side wallof a bore hole during the lowering of the assembly.

While I prefer to use a pliable rubber plug as the compression member,any plastic material, such as pitch, tar, rubber, cement of such weightas to form a distinct body, etc., would serve. Furthermore, I might usea rubber-covered cloth having the rubber of suflicient weight thereonthat when disposed inwardly, it would produce a body thick enough toprovide the desired sealing means, when drawn upon by an externalstrand, and it should be understood that the invention includes thiswithin its purview.

It is further to be understood that the invention includes within itspurview the thought of utilizing the Water proof fabric to housea maincharge of explosive either Having described my invention, what I claimis 1. An explosive assembly comprising an explosive cartridge, awater-proof fabric receptacle enclosing the same, a body of waterproofcompressible material within the fabric, a twisted wire strand forbinding the fabric forcibly upon said body, said strand terminating in aloop constituting a suspension means by which the assembly may belowered.

2. An explosive assembly comprising an explosive material, a water-prooffabric sheath for the same, a body, of water-proof compressible materialwithln the sheath of considerably smaller diameter than the sheath, atwist ed wire strand for drawing the fabric forcibly upon the body ofthe compressible material and loops in which said wire terminates, saidloops constituting means for suspending the assembly, as andfor thepurposes set forth.

3. An explosive assembly of the character described, comprising a bodyof explosive material, a tubular fabric sheath for the same having arubberized side disposed inwardly, a plug of waterproof and compressiblematerial of considerably smaller diameter than the diameter of thesheath, disposed in a gathered, open end of said sheath and a That is tosay, the explosive may said wire strand being bent into substantially Ilongitudinal alignment with the body of the sheath and terminating in asuspension means for the assembly.

4. An explosive assembly of the character.

' outer surface of said sheath.

5. An explosive assembly of the character described comprising a body ofexplosive material, a sheath for the same of waterproof material, acompressible waterproof plug disposed in an open end of said sheath,

'and an external binding means extending entirely around said sheath andplug and drawing the material of the sheath snugly against the plug atall points, said plug being of such materially smaller diameter than thesaid sheath that the drawing means and those portions of the sheathwhich are drawn against the plug will lie wholly inwardlyof the plane ofthe outer surface of the sheath, but said plug being of suflicientlygreat diameter that the extent to which the sheath is gathered to bebrought into contact therewith will not be enough to leave channelsthrough the sheath along the plug, whereby the assembly is adapted foruse in a bore hole under water and under pressure.

In testimony whereof I aflix my signature.

WILLIAM R. FARREN.

twisted wire strand compressing the material of the sheath forciblyagainst and into the material of the plug, a terminal end of

